Lamp assemblies are commercially available in which the relative positions of the lamp and the reflector are so fixed at the point of manufacture as to maximize output radiation intensity. Such units are employed in a wide variety of applications, typically for the production of ultraviolet radiation used, for example, in effecting the curing of photoinitiated adhesives and coating compositions. Presently available assemblies of this kind are not however entirely satisfactory from a number of standpoints.
The lamps utilized are generally of an elongate shape, with the electrical contacts on opposite end portions of the envelope and the emitting element (e.g., the arc of a mercury vapor lamp) centrally disposed therebetween. Heretofore, such lamps have been mounted with their longitudinal axes coincident with the central axis of the associated reflector, such that one of the end portions extends inwardly and is affixed within the reflector body with the opposite end portion extending outwardly in front of the reflective cavity. Not only is manufacture difficult, and the resultant assemblage somewhat insecure from a structural standpoint, but also such an arrangement may be impractical for certain lamps; i.e., the longer it is (e.g., the length of a 100-watt lamp, versus that of a 50-watt lamp) the deeper the reflector would have to be to accommodate it. Moreover, the conventional mounting undesirably disposes one of the electrical connections in the path of irradiation, and disposes the lamp itself in a horizontal attitude in normal use; vertical orientation is believed to extend bulb life, at least to some degree.